"Some people are more attractive to mosquitoes than others," said Robin Todd, director of Baltimore-based Insect Control and Research.

Todd and other scientists are not sure why mosquitoes bite some people and not others, but they have some theories.

Scientists believe mosquitoes are drawn to the carbon dioxide that people exhale. They are attracted to body heat and dark colors.

Todd said women are more often bitten by mosquitoes than men.

"Mosquitoes like the floral scents found in many women's perfumes," Todd said.

That, coupled with Todd's theory that women usually have more skin exposed in their summer wardrobe than men, can make women a mosquito smorgasbord.

Mosquitoes have long antennae on their heads that have very fine sensory hairs. Those follicles detect odor, heat and water vapor, Todd said.

Male and female mosquitoes readily drink nectar from plants, but only the females pierce the skin and drink blood, Todd said.

Some mosquitoes prefer the blood of birds and other animals to that of humans, he said.

Pete Money, director of education for the Virginia Living Museum, said mosquitoes are repelled by light.

That's why mosquitoes emerge at dusk. At a backyard barbeque, citronella candles can decrease a person's chances of being bitten, Money said.

"But you would have to put a candle in your pocket and one on your head to keep mosquitoes completely away," he said.

Money does not advise this.

When a mosquito bites, the common reaction in the human body is a raised bump or welt. Some people itch as a result of the bite, which is generally an allergic reaction to the mosquito's saliva, said Sally Paulson, associate professor of entomology at Virginia Polytechnic Institute in Blacksburg.

Although some species lay eggs without feeding on blood, most require a blood meal to mature their eggs, Paulson said.

Mosquitoes lay their eggs in or near stagnant pools of water.

Anywhere that fish do not live can be their breeding ground, including tires filled with rainwater, garbage cans or a child's beach pail, said Jim Rhindflesh, a biologist with York County Mosquito Control.

A mosquito's bite is not only annoying, it can be harmful.

"Mosquitoes are more dangerous to the health of humans than any other group of insects," said Gary Clark, an entomologist with the Center for Disease Control in San Juan, Puerto Rico.

In the tropics and subtropics, mosquitoes can carry several types of diseases, including malaria, which can cause high fever, chills, and often death, Clark said.

There is no evidence that mosquitoes transmit the AIDS virus, Clark said.

In the United States, mosquitoes can carry many types of encephalitis, a disease marked by flu-like symptoms.

Mosquitoes in the United States are more of a nuisance than a deadly insect, Todd said.

"Mosquitoes serve very little purpose, except that they are snacks to certain birds and amphibians," Todd said.

Each summer Rhindflesh and his staff from mosquito control, wipe out several hundred pounds of mosquitoes in problem areas.

Next week, a C-130 from Youngstown, Ohio, will fly into Langley Air Force Base to do an annual aerial spraying of the base, parts of Hampton, Newport News, Poquoson and York County.

"To avoid being bitten by mosquitoes, one should wear insect repellent," said Gary Dunn, director of education for the Michigan-based Young Entomologists' Society. "It also doesn't hurt to hope the mosquitoes like your friend better than they like you."

HOW TO AVOID MOSQUITO BITES

To avoid being bitten by mosquitoes, entomologists offer the following tips: